金属切削毛刺形成的有限元模型及机理分析

The Finite Element Model and Mechanism Analysis for Burr Formation in Metal Cutting

金属切削毛刺是影响精密零件棱边质量及使用性能的主要因素之一.本研究建立了毛刺形成的有限元模型,并根据其模拟结果分析了毛刺形成的机理,由此将毛刺形成分为三个不同形成机理的阶段.提出了负剪切角及负变形区的概念.在本有限元模型中提出并应用了基于材料失效的切屑分离准则.模拟结果与试验结果进行了比较,取得了教好的吻合.本模型的建立为分析毛刺的形成机理及定量预报提供了一种有意义的探索途径.

Metal cutting burr is an important factor of influence to edge quality and performance of precision parts. A burr formation FEM has been presented in this paper. From the simulation results of strain and stress distribution, the mechanism of the burr formation process is analyzed. Also, three different stages in burr formation process which have different mechanism have been studied. A chip separation criterion based on the critical value of the strain failure is introduced into the analytical model. The concept of negative shear zone and negative shear angle are proposed in study. Results of simulation are close to that[KG-*2]’[KG-*5]s of experiment. Finite element model generated here provided a numerical analysis method to solve the prediction of burr formation and physical insight into the fundamental burr formation mechanism.